Network simulations allow mobile network operators to analyze the effects of different network events (e.g., changeover from one type of wireless network equipment to another) and implementations (e.g., wireless coverage into different areas) prior to installation, upgrade, or reconfiguration of the wireless network components. In discrete-event simulations of networks that include radio access networks such as, for example, long term evolution (LTE) or Wi-Fi, it is desirable in the interest of error modeling fidelity to be able to simulate down to the level of the data transmission of each bit. However, such bit level simulation becomes impractical in network models with a substantial number of wireless network links, network routers, base stations, access points, and user equipment (UE), due to the computational costs in time and data storage space. Simply stated, the large amount of data generated by a large scale bit-level simulation is prohibitive both in time and cost.
While bit-level simulators for LTE systems do exist, their use in the industry is necessarily restricted due to significant volumes of data storage and computation time/resources required to implement even the small simulation models that include, for example, a single eNodeB, or cell, and perhaps two or three UE devices. In such small simulation models, there are only a small number of interfering radio channels to be simulated; and while simulation at the bit level can be practical, the simulation of larger networks in this manner is impractical.
An alternate approach to bit-level simulation is a discrete-event system-level approach. In a discrete-event system-level simulation the bit errors may be extrapolated to a system level error rate by assuming that the error rate is constant in time or random over system level frames. However, this extrapolated system level error rate produces random errors disburst in randomly in time in the simulation results which is not a realistic portrayal of network performance.
Accordingly, present discrete-event system-level simulations are at a disadvantage because using an assumption that the error rate is constant in time or even purely random typically leads to an overestimation of system-level performance. A deployment based on such an overestimation often will not perform as well as predicted by the simulation. As a result, the adoption of a constant frame error rate target in system-level simulation modeling of LTE systems limits the practical validity of the system-level simulation results. For example, overly optimistic estimates of data throughput, latency, a number of dropped packets, packet errors, out-of-order frame delivery, and jitter may be provided by the above referenced system-level simulation techniques. The overly optimistic estimates result in an expected network performance that for some applications (e.g., streaming video, on-line gaming and voice over IP applications) provides the user with a less than satisfying experience with the application and communication network.
Hence, the need for a practical system level simulation that accounts for burst errors remains.